


Flukes

by owlady



Series: Whales and Bats both Echolocate [2]
Category: Batman (Comics), Batman - All Media Types, Batman Beyond
Genre: F/M, Gen, Mer AU, inspired by thecreativecasserole's oneshot!, repeatedly, terry often gets smacked into walls in canon and now he's getting dunked into the sea
Language: English
Status: Completed
Published: 2020-08-05
Updated: 2020-08-05
Packaged: 2021-03-06 02:35:37
Rating: Teen And Up Audiences
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 3,781
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25726018
Author URL: https://archiveofourown.org/users/owlady/pseuds/owlady
Summary: The Jokerz are gone, and Terry doesn’t know where they went- all he knows is that he’s stopped swimming and he’s looking out over the water. It’s black and white and dark, but he’s pretty sure-There’s a mer in the water. There is a mer in the water,  and it’s the size of an orca whale. It is floating like a dead fish- there is a dark, angry black mark across it’s chest and it smells like burning skin and fat.Terry’s eyes widen, and then he kicks even more furiously for shore.
Relationships: Terry McGinnis & Bruce Wayne, Terry McGinnis/Dana Tan
Series: Whales and Bats both Echolocate [2]
Series URL: https://archiveofourown.org/series/2000107
Comments: 9
Kudos: 54





	Flukes

**Author's Note:**

  * For [TheCreativeCasseroles](https://archiveofourown.org/users/TheCreativeCasseroles/gifts).



Gotham is a harbor City.

It’s next to the ocean- the docks are long, crammed together, and lined with boats and sailors and people who would sooner shoot you and dump you in the water than say hello. They have horrible storms, awful summers, and worse winters, and it can all be traced back to the ocean.

Some say it can all be traced back to the Bat, but Terry’s not into cryptids.

All the good things in Gotham come from the sea, too- the rolling waves, the rounded pebbles, the quiet beach nooks, the pods of whales in the early spring that migrate nearby. And Terry is a Gotham boy, practically born in the water- his mom’s always been confused at his ability to hold his breath for almost five minutes when both she and his father, Warren, can barely reach two without having to come back up for air. The ocean’s where he’s at home. Or it used to be, before his mom and dad divorced, Terry made some bad choices, and spent three months in juvenile detention. Miles away from the water, he just… dried up.

His dad bailed him out of the facility. His dad, the Marine Scientist.

Same guy who was all over Terry’s back about being grounded, and for what? Punching a guy who deserved it, who literally spat on him in the middle of gym class?!

Yeah, right. Screw that.

There’s a party, tonight. A beach rager, clambake, whatever old shway word you wanna call it, and there’s going to be a bonfire and music and idiot teenagers with alcohol. Terry is  _ going _ . Terry is meeting up with Dana, and Terry couldn’t give two shakes what his old man thinks of him ditching an undeserved grounding. Yelling at his dad wasn’t right, Terry knew that- but it felt good, when his dad wouldn’t listen and Terry hadn’t done something wrong. It was freakin’  _ Nash _ . Who wouldn’t hit Nelson Nash?

Even Warren McGinnis would’ve wanted to pop the guy one, if he’d ever met him for more than half a minute.

For the first time in a long time- maybe a year- Terry McGinnis is going to the beach, and he’s going to have fun. Heck, he might even swim. Though he’s definitely out of practice.

* * *

He’s got his jacket on, brown leather mimic that he’s always had a soft spot for, and under that he wears his old surfing wetsuit. It’s short in the knees and sleeves by design, but for a little beach party it should hold up. Dana’s definitely going to be there in something summery, he thinks, and his mind drifts as he catches the train to the bay. Sandals, jeans- the night is cold, but Terry’s still young. He’s bright enough to burn off the chill if it gets to him.

He has to walk another half a mile to get to the spot that was pinned for the party, but it’s worth it when he sees Dana, Max, and Chelsea all sitting in the sand, sharing a red blanket as their chair. Actually, Terry barely sees Max and Chelsea- he’s focused on Dana, who’s wearing a two piece with some kind of skirt, tied to the side, and damn, if he isn’t enchanted by her more than he usually is. 

She shrieks with laughter when he comes up next to her, seeing him out of the corner of her eye. He kisses her cheek, and she holds his hand, and Terry wonders how the hell he ever got someone like Dana Tan to fall for someone like him.

High school romances don’t always last, but he’s fallen deep. Not to sound like a dope, or anything- that’s how Terry is. Big emotions.

“I thought your dad grounded you!” Dana pulls him down further, so he’s also on the red blanket, and the fleece of it tickles his palm as he settles down to balance.

“I gave myself time off for good behavior,” he grins, and rests his forehead against hers. “Told you I’d make it.”

“If you’d stop trying to rearrange Nelson’s face, I wouldn’t have to worry,” Dana points out. Chelsea sighs.

“The list of people who haven’t punched Nelson Nash in the face is shorter than the list of people who have,” Max points out, and she’s sipping some kind of soda while she watches the coast. Nelson is also at this party, unfortunately, and he’s being held upside down over the keg of drink someone brought. Terry thinks it’s a waste of a good time-

And then there’s a loud noise, in the distance.

Terry’s a Gotham boy, and he knows that sound. It’s jetskis, probably boosted. He turns to look out at the ocean, hand tight around Dana’s, and his grip is enough to make her pause in the middle of what she’s saying to look at him.

“Terry?”

He almost doesn’t say anything, standing up to get a better look further out. “Did you guys hear-”

None of the girls respond that they did, and it takes almost twenty seconds before the sound of roaring engines gets loud enough that everyone stops the party. Lights flash across the beach, bright and strobing, and when the skis cut out, laughter fills the air.

Not the good kind.

It’s a school of Jokerz.

They’re painted bright, poisonous clownfish colors. The leader’s got white paint on, waterproof, and fake green fins. The others- there’s at least ten, slaggit, Terry hates this- have other colors, and they’re covered in spines, nets, anchors, fish hooks. The lone girl in the gang is covered in what looks like fake sea anemones- but if Terry knows the Jokerz, they burn just like the real thing. If not worse.

Pirates, vandalists, dregs. Whatever you want to call them, Jokerz are a pain on a good day and worse when Terry isn’t even wearing thick-soled shoes to protect him from the sharp weapons they’re wearing. If he has to start kicking, it’s going to be hell with the sand and the seawater and the still having to walk home.

Nelson gets dropped on his face, and Terry would enjoy it more if Nash, half-drunk, wasn’t stumbling around and looking for a fight with the first person he saw.

Who happened to be a Joker. Emerging from the water like some ancient b-movie fish monster, cackling.

“Hey, get outta here,” Nelson lashes out, shoving, and the Jokerz are  _ armed _ , god. Terry’s taken off his jacket and made sure Dana’s put it on- He’s wearing more layers than she is, and the leather will keep her safe if someone decides things have to get nasty tonight.

He’s about to make sure that Chels wraps herself in the red blanket for the same reason (Max is wearing a longsleeved hoodie and leggings, which is more protection than Chels has in a onepiece and bare feet) when the Jokerz crow and one of them is suddenly right up next to Dana. Right up next to Max, and holding Chelsea’s arm.

Terry does the only thing he can think to do, at this exact moment- he punches the Joker straight in the face, and he goes down hard. Piercings and fishhooks and ocean flower boutonniere aside, it was pretty clean. Barely even bleeds.

The effect on the party and the rest of the Jokerz is a lot stronger. Even with Nelson trying to duke it out with the leader, he gets shoved back easy. The rest of the people at the party group up into big circles, with the braver ones on the outside against the threat.

“Hey,” says the leader who has just laid out Nash Nelson. “It’s that guy. The one you were talking about.”

“No fun boy,” the guy he’s talking to nods, and slag, that dreg’s the same one Terry took down earlier that day. He’s got the lobster claws and stupid antennae hat to prove it. “Couldn’t even let me make a joke!”

And Terry realizes he is so, so slagged it is not even funny. Maybe he could fight back against two or three- but against ten, with weapons and get-away vehicles? Plus all of his classmates and his girlfriend at risk?

He’d swear if his mom hadn’t trained the habit out of him to keep Matty’s innocence alive and well.

“Call the police,” he says, and Chelsea nods as Max pulls out her phone and ducks behind her. Dana grips his wetsuit, drowning in his jacket.

“I know that look,” she hisses. “Terry, they’re Jokerz! It’s ten to one!”

And Terry feels his heart do this weird throb. He’s not the type to stop, not over this, but she’s still the one who will try to keep him from doing something incredibly dangerous.

“I have a plan. And you’re the one who knows the most people here- when you get an opening, you’re the one who’s going to have to get everyone off the beach and to the cops before someone gets hurt. They’ll listen to you, Dana.”

And she breathes through her nose, worried. But Terry’s already taking advantage of the fact that she’s distracted and he pulls away to stalk down the beach. 

“Terry!”

“You really shouldn’t show up at parties you’re not invited to,” Terry says, letting just a little humor bleed into his voice. It’s a warning, a joke, and a threat, all at once.

“And who’s gonna stop us, no fun boy?” Says the leader. “You?”

Someone levels a harpoon gun at him. Probably loaded with laser rounds, which are impossible to dodge and cauterize instantly- it’s nasty tech. “You don’t have a chance.”

And Terry is ready for part 2 of plan ‘Give Dana Gray Hairs’: aggravate the Jokerz. Well, aggravate them more.

He slashes out with a leg, and sweeps the leader. Then he lances forward with a two-punch combo, and it sends his second down to the sand. Behind him, the partygoers are fleeing, and the Jokerz are swarming- and Terry knows he has to run. He undoes the button to his jeans and then sprints into the surf, water pressing against him like it wants him to stay out of the ocean until it’s up to his waist. Then he dives, deep enough to swim under waves. Jokerz follow, but they have to swim too to get out to Terry’s target- the boosted jetskis. And Terry, despite being rusty, is  _ fast _ in the water. It’s like he was built for it.

He kicks and loses his jeans to the ocean, sandals slipping away with them. But his phone was in his jacket- which Terry’s glad he gave to Dana, now- and it takes only a second or two to haul himself up onto the closest jetski, though the Jokerz are close behind. It takes a second to figure out how to work it- ignition, brake- but as soon as he’s got the basics, he fishtails in a wide circle. It sprays salt everywhere and he hauls ass, just trying to get as much distance between the Jokerz and his friends as he possibly can.

* * *

Thirty minutes later, they’re still chasing him.

There’s a heavy storm on the horizon, and it’s chopping up the water dangerously. Terry’s almost at empty and the only land in sight is Wayne Bluff- the old cliffside mansion looking out over the ocean. There’s a beach underneath, but Terry isn’t going to make it with the amount of fuel he’s got left. He could swim it- but a jetski is faster than any human being, and if he gets run over by one it will seriously maim him.

It’s a fifty fifty chance, Terry thinks- Jetski propeller blades or getting the slag beat out of him and left bleeding on some private beach that nobody ever visits. Dana, Chels, and Max are safe- hell, even Nelson Nash is safe, and the rest of their class, but not him.

Shreds, he’ll take the beach, he thinks. If he’s going down, he’s going down fighting, not by getting held under a propeller blade until he’s barely even fish food. He lets go of the ignition and slows to a stop sideways, so he has the most cover possible-

Terry jumps in.

He’s maybe a mile from that beach, and he’s out of practice swimming. But he’s got his wetsuit, so he’s not losing body heat- not much, he thinks, teeth gritted against the cold.

“End of the line!” Someone screams over the roar of the engines, and Terry swims, feeling terror clutch at him. Anger, too. Because  _ hell  _ if a bunch of Jokerz are going to kill him before he even turns 16! He isn’t going out like that!

He lets out a low sound, bubbles escaping from his mouth, and then he panics, hacking and coughing as he hauls through the surface of the water. Terry slips under, cursing, and tries to hold his breath for as long as he can-

But seven minutes doesn’t work when you’ve just committed to trying to swim a mile for your life.

His chest is screaming. He’s screaming. He’s underwater and he’s made a terrible, loud sound (loud to him, his heart thudding in his ears)- 

There is an enormous dark shape in the water ahead of him. Terry thinks this is it- this is how he dies, Gotham boy, drowned in the harbor. Didn’t even hold his breath right. The water echoes with the sound of currents, Jokerz muffled laughter, and…

Whalesong?

It can’t be, Terry thinks. Whalesong is so loud on the decibel scale that it can be weaponized. It can shatter eardrums. If a whale was right behind him, he would be deaf.

But someone takes his hand and Terry finally finds which way is up, gasping for air and righting himself. He cuts at the water, still headed for the beach- survive, survive, survive!

Back with the Jokers, he can hear a booming, gravely voice say “This is private property. Get out of here.” Terry’s main concern is getting to land, not whatever kind of nutso hallucination he’s having right now, no matter how helpful it’s being with the angry gang that wants to kill him.

He’s been swimming for almost twenty minutes, and can see where the sea evens out into the private beach. There’s a CLAP, and a BOOM, and thunder and lightning crash over the ocean and strike something truly huge. The Jokerz are gone, and Terry doesn’t know where they went- all he knows is that he’s stopped swimming and he’s looking out over the water. It’s black and white and dark, but he’s pretty sure-

There’s a mer in the water. There is a  _ mer _ in the  _ water,  _ and it’s the size of an orca whale. It is floating like a dead fish- there is a dark, angry black mark across it’s chest and it smells like burning skin and fat.

Terry’s eyes widen, and then he kicks even more furiously for shore.

There’s a giant mer underneath the old Wayne Bluff, and it’s been struck by lightning. A creature barely even documented, and it just saved his life. Slag it.

Terry’ll be lucky to make it up to the mansion for help before its heart stops.

There’s an elevator installed at the base of the cliff, for some reason, but it won’t open when Terry hits the button. So instead he just takes the stairs up from the bottom two at a time, getting splinters in his shins and feeling that sense of urgency he’s had for the past two hours reach its peak. He really hates adrenaline, sometimes- if he crashes now, it’s going to be ugly.

The beach path leads right up to the old mansion, but there’s a heavy iron gate in Terry’s way. There’s no time for this, he groans, and just jumps to grab the top and hauls himself over, landing in a painful crouch on the other side.

No phone, no phone, no phone. Dying mer. Jokerz. Terry needs to find a phone, and now!

He slams his arm against the first door he finds- it’s a little side door off the edge of some vegetable garden. Probably leads into the kitchens- if Terry’s lucky, someone will be up at 2 AM, hoping for a late night snack.

Terry isn’t lucky. Nobody answers, so he sprints around the side of the manor to find another door, out of breath within minutes as he hits the knocker against the huge double doors.

Finally, someone answers- but they aren’t friendly. In fact, they’re irate, and oh, look. While Terry was busy trying to get air into his lungs, they grabbed him round the neck. “Who are you?!”

Terry’s a mess. He’s wearing an old, patched black wetsuit, he’s out of breath, and he looks like he’s been hit by a truck at least once. He wheezes, then makes the same noise he made before when he was drowning. It sounds like a cross between a broken squeaky toy and a loud clap.

Whoever it is, framed in shadow, lets go like they’ve been burned.

“Mer!” He gasps out. “Beach!”

“What?!” he hears, and the sound is a little fuzzy all around. There might be some kind of accent, he thinks. Or that’s just the exhaustion.

“Mer on the beach,” Terry says, and then closes his eyes. “Got hit. Lightning.”

A foot slams into his stomach, and Terry heaves, feeling sick. It doesn’t happen again, though, and that wasn’t a kick, so what the hell even-

He hears running.

...The owner of the mansion literally just ran over him to get to the mer on the beach and left him sprawled across the front steps. Terry passes out. What kind of person just runs OVER someone?

The same kind of person who doesn’t come back by the time Terry wakes up, it seems.

* * *

He’s out for at least half an hour- or so Terry guesses. The door is left open, and a cat and dog are both sniffing at him curiously when he comes to. The dog is enormous, some kind of german shepherd, maybe- and the cat is average, black with white paws. He tries to sit up- only to feel all sorts of pain in his stomach and lie back down. The dog licks his hand, and Terry whines. Oh, man. Facing his dad like this is gonna suck- the old man’s never gonna let him hear the end of it-

Wait. His dad.

Terry staggers up. It’s been  _ hours _ , and despite the way the two of them parted earlier before the beach party, he has to call his dad. He knows his dad’ll be worried- and this is the only place that has a phone he can use for miles.

He spends twenty minutes searching for an office or a usable landline, only to hit paydirt in a roomy office lined with bookshelves. Trophies. Antiques. There’s an incredible clock along the wall inscribed with fish and waves, and the pendulum at the bottom is shaped like a mer-

A flash catches Terry’s eye, even as he’s dialing on the old phone (the buttons are clunky, physical. Way retro). He looks, holding the phone up to his ear, and the dial tone buzzes. Over, and over, it buzzes, and there’s a bat stuck in the clock.

It’s squeaking. It looks exhausted, like it’s been fighting to get someplace safer for a while.

Terry can relate to that.

His call goes to voicemail, so he puts down the old receiver.

“I’ll get you out of there,” Terry says softly, and then adds, “Just don’t bite me,” as a sort of ward against getting even more cuts and bruises than he already has. He feels around the clock for any kind of button or latch, and manages to open the casing and pull aside the pendulum.

It sticks, so he tries to wiggle it. The bat needs room to get out.

Then the clock swings out, and the back is  _ fake _ . The bat was trapped against some kind of sliding door and this clock’s face. As soon as the clock is out of the way that door slides open, and Terry is left staring down a long, deep set of stairs. Water reflects light onto the ceiling further down.

Hypnotized, he takes a step forward, following the little bat as it flies inwards. Then another, and another, until finally he’s out standing on some kind of ledge- a huge metal dock, really. He can see over and it is a nautical  _ wonderland _ .

Said wonderland is bat-themed.

There is a bat-submarine. A bat-computer. A bat-lab. Tons of ocean debris, polished and dusted like trophies- there’s a giant penny just standing there, and Terry has to gape at the sheer size of this place. It’s a cave dedicated to… to what, he asks, until he turns again and sees a line of tubes up against the wall. They’re filled with water.

Floating in each chamber there’s a necklace. From left to right, carved coral and gemstone in the shape of bats, birds, fish, and shells. They’re all glowing, and Terry knows what this cave is.

This cave is the hideout of the legendary Bat. Gotham’s merman, defender of the bay, and rumored friend of the king of Atlantis himself- Aquaman.

Terry can barely breathe, but not for a lack of air. The cement floor is cold against his frozen toes, but he can’t stop as he gets within arm’s reach of these beautiful necklaces.

They sing to him. Terry can hear their song.

A finger brushes a bright red bat, made of shaped sea glass-

It’s beautiful. It sounds like the ocean.

“It’ll be okay, Bruce,” someone says, and Terry startles so badly that he cuts himself on the necklace, his blood wisping out around it. “We’re calling Grayson, and Todd has already gone to retrieve aid from Atlantis-”

He pulls back, and tries not to make a sound, but the splash of his hand leaving the necklace’s tank is loud. The cave goes silent, but not like it was earlier- he can hear the labored breathing of who he assumes is the Bat Mer who had been hit by the storm, and then someone leaps out of the water and Terry falls over the railing, screeching. His hand is still wrapped tight around the bat, stinging and hurting.

Terry hits the water.

Terry doesn’t remember anything after that.

* * *

He wakes, drenched, at the side of the river near his apartment.

He is still holding the bat pendant. 

The cut on his palm is gone, as if it never even existed.

**Author's Note:**

> mermay in august? why not IVE BEEN PUTTING THIS OFF FOR MONTHS


End file.
